At its heart, the scandal involves the Diplomatic Security Service (DSS), the body responsible for protecting the secretary of state and U.S. ambassadors who are serving in foreign countries. The DSS is also tasked with overseeing investigations into misconduct of State Department employees, CBS reports.

CBS News’ John Miller reports that according to an internal State Department Inspector General’s memo, several recent investigations were influenced, manipulated, or simply called off. The memo obtained by CBS News cited eight specific examples. Among them: allegations that a State Department security official in Beirut “engaged in sexual assaults” on foreign nationals hired as embassy guards and the charge and that members of former Secretary of State Hillary Clinton’s security detail “engaged prostitutes while on official trips in foreign countries” — a problem the report says was “endemic.”

The memo also reveals details about an “underground drug ring” [that] was operating near the U.S. Embassy in Baghdad and supplied State Department security contractors with drugs.

Aurelia Fedenisn, a former investigator with the State Department’s internal watchdog agency, the Inspector General, told Miller, “We also uncovered several allegations of criminal wrongdoing in cases, some of which never became cases.”

The Inspector General’s office was apparently told by DSS agents that senior State Department officials wanted them to ignore or back away from specific cases. If this is the case, it is likely that many will alleged a cover-up was underway. Fedenisn called the level of purported pressure and influence from higher-ups “very disturbing.”

In one example, State Department agents claim that they were told not to investigate a U.S. ambassador who was suspected of seeking out prostitutes in a public park. In a memo, the ambassador is said to have regularly “ditched” his detail in an effort to gain sexual favors from these women.

“I mean my heart really went out to the agents in that office, because they really want to do the right thing, they want to investigate the cases fully, correctly, accurately … and they can’t,” said Fedenisn, a DSS agent for 26 years and a whistle-blower who has prepared a draft report about these alleged abuses.

Watch the CBS News report, which documents these allegations in detail: